Add structopt dependency in version 0.3.7

This patch series replaces argparse with structopt in the argument handling code. As a first step, we need structopt as a dependency. Import subrepo structopt/:structopt at efbdda4753592e27bc430fb01f7b9650b2f3174d Import subrepo bitflags/:bitflags at 30668016aca6bd3b02c766e8347e0b4080d4c296 Import subrepo clap/:clap at 784524f7eb193e35f81082cc69454c8c21b948f7 Import subrepo heck/:heck at 093d56fbf001e1506e56dbfa38631d99b1066df1 Import subrepo proc-macro-error/:proc-macro-error at 6c4cfe79a622c5de8ae68557993542be46eacae2 Import subrepo proc-macro2/:proc-macro2 at d5d48eddca4566e5438e8a2cbed4a74e049544de Import subrepo quote/:quote at 727436c6c137b20f0f34dde5d8fda2679b9747ad Import subrepo rustversion/:rustversion at 0c5663313516263059ce9059ef81fc7a1cf655ca Import subrepo syn-mid/:syn-mid at 5d3d85414a9e6674e1857ec22a87b96e04a6851a Import subrepo syn/:syn at e87c27e87f6f4ef8919d0372bdb056d53ef0d8f3 Import subrepo textwrap/:textwrap at abcd618beae3f74841032aa5b53c1086b0a57ca2 Import subrepo unicode-segmentation/:unicode-segmentation at 637c9874c4fe0c205ff27787faf150a40295c6c3 Import subrepo unicode-width/:unicode-width at 3033826f8bf05e82724140a981d5941e48fce393 Import subrepo unicode-xid/:unicode-xid at 4baae9fffb156ba229665b972a9cd5991787ceb7
author: Robin Krahl <robin.krahl@ireas.org> 2020-01-07 11:18:04 +0000
committer: Daniel Mueller <deso@posteo.net> 2020-01-08 09:20:25 -0800
commit: 5e20a29b4fdc8a2d442d1093681b396dcb4b816b (patch)
tree: 55ab083fa8999d2ccbb5e921c1ffe52560dca152 /proc-macro-error
parent: 203e691f46d591a2cc8acdfd850fa9f5b0fb8a98 (diff)
download: nitrocli-5e20a29b4fdc8a2d442d1093681b396dcb4b816b.tar.gz
nitrocli-5e20a29b4fdc8a2d442d1093681b396dcb4b816b.tar.bz2
43 files changed, 2120 insertions, 0 deletions
diff --git a/proc-macro-error/.gitignore b/proc-macro-error/.gitignore
new file mode 100644
index 0000000..9d538f2
--- /dev/null
+++ b/proc-macro-error/.gitignore
@@ -0,0 +1,4 @@
+/target
+**/*.rs.bk
+Cargo.lock
+.fuse_hidden*
+\ No newline at end of file
diff --git a/proc-macro-error/.gitlab-ci.yml b/proc-macro-error/.gitlab-ci.yml
new file mode 100644
index 0000000..e36a714
--- /dev/null
+++ b/proc-macro-error/.gitlab-ci.yml
@@ -0,0 +1,54 @@
+stages:
+  - test
+
+
+.setup_template: &setup_template
+  stage: test
+  image: debian:stable-slim
+  before_script:
+    - export CARGO_HOME="$CI_PROJECT_DIR/.cargo"
+    - export PATH="$PATH:$CARGO_HOME/bin"
+    - export RUST_BACKTRACE=full
+    - apt-get update > /dev/null
+    - apt-get install -y curl build-essential > /dev/null
+    - curl https://sh.rustup.rs -sSf | sh -s -- -y --default-toolchain $RUST_VERSION
+    - rustup --version
+    - rustc --version
+    - cargo --version
+
+.test_all_template: &test_all_template
+  <<: *setup_template
+  script:
+    - cargo test --all
+
+
+test-stable:
+  <<: *test_all_template
+  variables:
+    RUST_VERSION: stable
+
+test-beta:
+  <<: *test_all_template
+  variables:
+    RUST_VERSION: beta
+
+test-nightly:
+  <<: *test_all_template
+  variables:
+    RUST_VERSION: nightly
+
+
+test-1.31.0:
+  <<: *setup_template
+  script:
+    - cargo test --tests # skip doctests
+  variables:
+    RUST_VERSION: 1.31.0
+
+test-fmt:
+  <<: *setup_template
+  script:
+    - cargo fmt --all -- --check
+    - RUTSFLAGS='--cfg nightly_fmt' cargo fmt --all -- --check
+  variables:
+    RUST_VERSION: stable
diff --git a/proc-macro-error/.travis.yml b/proc-macro-error/.travis.yml
new file mode 100644
index 0000000..362003f
--- /dev/null
+++ b/proc-macro-error/.travis.yml
@@ -0,0 +1,19 @@
+language: rust
+rust:
+  - stable
+  - beta
+  - nightly
+script:
+  - cargo test --all
+matrix:
+  include:
+    - rust: 1.31.0
+      script: cargo test --tests # skip doctests
+  allow_failures:
+    - rust: nightly
+  fast_finish: true
+
+
+notifications:
+  email:
+    on_success: never
diff --git a/proc-macro-error/CHANGELOG.md b/proc-macro-error/CHANGELOG.md
new file mode 100644
index 0000000..29043b5
--- /dev/null
+++ b/proc-macro-error/CHANGELOG.md
@@ -0,0 +1,86 @@
+# v0.4.4 (2019-11-13)
+* Fix `abort_if_dirty` + warnings bug
+* Allow trailing commas in macros
+
+# v0.4.2 (2019-11-7)
+* FINALLY fixed `__pme__suggestions not found` bug
+
+# v0.4.1 (2019-11-7) YANKED
+* Fixed `__pme__suggestions not found` bug
+* Documentation improvements, links checked
+
+# v0.4.0 (2019-11-6) YANKED
+
+## New features
+* "help" messages that can have their own span on nightly, they
+    inherit parent span on stable.
+    ```rust
+    let cond_help = if condition { Some("some help message") else { None } };
+    abort!(
+        span, // parent span
+        "something's wrong, {} wrongs in total", 10; // main message
+        help = "here's a help for you, {}", "take it"; // unconditional help message
+        help =? cond_help; // conditional help message, must be Option
+        note = note_span => "don't forget the note, {}", "would you?" // notes can have their own span but it's effective only on nightly
+    )
+    ```
+* Warnings via `emit_warning` and `emit_warning_call_site`. Nightly only, they're ignored on stable.
+* Now `proc-macro-error` delegates to `proc_macro::Diagnostic` on nightly.
+
+## Breaking changes
+* `MacroError` is now replaced by `Diagnostic`. Its API resembles `proc_macro::Diagnostic`.
+* `Diagnostic` does not implement `From<&str/String>` so `Result<T, &str/String>::abort_or_exit()`
+    won't work anymore (nobody used it anyway).
+* `macro_error!` macro is replaced with `diagnostic!`.
+
+## Improvements
+* Now `proc-macro-error` renders notes exactly just like rustc does.
+* We don't parse a body of a function annotated with `#[proc_macro_error]` anymore,
+  only looking at the signature. This should somewhat decrease expansion time for large functions.
+
+# v0.3.3 (2019-10-16)
+* Now you can use any word instead of "help", undocumented.
+
+# v0.3.2 (2019-10-16)
+* Introduced support for "help" messages, undocumented.
+
+# v0.3.0 (2019-10-8)
+
+## The crate has been completely rewritten from scratch!
+
+## Changes (most are breaking):
+* Renamed macros:
+  * `span_error` => `abort`
+  * `call_site_error` => `abort_call_site`
+* `filter_macro_errors` was replaced by `#[proc_macro_error]` attribute.
+* `set_dummy` now takes `TokenStream` instead of `Option<TokenStream>`
+* Support for multiple errors via `emit_error` and `emit_call_site_error`
+* New `macro_error` macro for building errors in format=like style.
+* `MacroError` API had been reconsidered. It also now implements `quote::ToTokens`.
+
+# v0.2.6 (2019-09-02)
+* Introduce support for dummy implementations via `dummy::set_dummy`
+* `multi::*` is now deprecated, will be completely rewritten in v0.3
+
+# v0.2.0 (2019-08-15)
+
+## Breaking changes
+* `trigger_error` replaced with `MacroError::trigger` and `filter_macro_error_panics`
+  is hidden from docs.
+  This is not quite a breaking change since users weren't supposed to use these functions directly anyway.
+* All dependencies are updated to `v1.*`.
+
+## New features
+* Ability to stack multiple errors via `multi::MultiMacroErrors` and emit them at once.
+
+## Improvements
+* Now `MacroError` implements `std::fmt::Display` instead of `std::string::ToString`.
+* `MacroError::span` inherent method.
+* `From<MacroError> for proc_macro/proc_macro2::TokenStream` implementations.
+* `AsRef/AsMut<String> for MacroError` implementations.
+
+# v0.1.x (2019-07-XX)
+
+## New features
+* An easy way to report errors inside within a proc-macro via `span_error`,
+  `call_site_error` and `filter_macro_errors`.
diff --git a/proc-macro-error/Cargo.toml b/proc-macro-error/Cargo.toml
new file mode 100644
index 0000000..6fa600e
--- /dev/null
+++ b/proc-macro-error/Cargo.toml
@@ -0,0 +1,7 @@
+[workspace]
+
+members = [
+    "proc-macro-error",
+    "proc-macro-error-attr",
+    "test-crate",
+]
diff --git a/proc-macro-error/LICENSE-APACHE b/proc-macro-error/LICENSE-APACHE
new file mode 100644
index 0000000..52ba334
--- /dev/null
+++ b/proc-macro-error/LICENSE-APACHE
@@ -0,0 +1,201 @@
+                              Apache License
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+TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
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+1. Definitions.
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+
+APPENDIX: How to apply the Apache License to your work.
+
+   To apply the Apache License to your work, attach the following
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diff --git a/proc-macro-error/LICENSE-MIT b/proc-macro-error/LICENSE-MIT
new file mode 100644
index 0000000..d01f775
--- /dev/null
+++ b/proc-macro-error/LICENSE-MIT
@@ -0,0 +1,21 @@
+MIT License
+
+Copyright (c) 2019 CreepySkeleton
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
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+SOFTWARE.
diff --git a/proc-macro-error/README.md b/proc-macro-error/README.md
new file mode 100644
index 0000000..d6d1086
--- /dev/null
+++ b/proc-macro-error/README.md
@@ -0,0 +1,206 @@
+# proc-macro-error
+
+[![travis ci](https://travis-ci.org/CreepySkeleton/proc-macro-error.svg?branch=master)](https://travis-ci.org/CreepySkeleton/proc-macro-error)
+[![docs.rs](https://docs.rs/proc-macro-error/badge.svg)](https://docs.rs/proc-macro-error)
+
+This crate aims to make error reporting in proc-macros simple and easy to use.
+Migrate from `panic!`-based errors for as little effort as possible!
+
+Also, there's ability to [append a dummy token stream][crate::dummy] to your errors.
+
+```toml
+[dependencies]
+proc-macro-error = "0.4"
+```
+
+*Supports rustc 1.31 and up*
+
+[Documentation and guide][guide]
+
+## What emitted errors look like
+
+```
+error: multiple error part: multi2
+
+  = note: help message test
+  = help: Option help test
+  = note: I see what you did here...
+
+ --> $DIR/multi-error.rs:4:18
+  |
+4 | make_fn!(multi1, multi2, _, multi3);
+  |                  ^^^^^^
+```
+
+## Examples
+
+### Panic-like usage
+
+```rust
+use proc_macro_error::*;
+use proc_macro::TokenStream;
+use syn::{DeriveInput, parse_macro_input};
+use quote::quote;
+
+// This is your main entry point
+#[proc_macro]
+// this attribute *MUST* be placed on top of the #[proc_macro] function
+#[proc_macro_error]
+pub fn make_answer(input: TokenStream) -> TokenStream {
+    let input = parse_macro_input!(input as DeriveInput);
+
+    if let Err(err) = some_logic(&input) {
+        // we've got a span to blame, let's use it
+        // This immediately aborts the proc-macro and shows the error
+        abort!(err.span, "You made an error, go fix it: {}", err.msg);
+    }
+
+    // `Result` has some handy shortcuts if your error type implements
+    // `Into<MacroError>`. `Option` has one unconditionally.
+    more_logic(&input).expect_or_abort("What a careless user, behave!");
+
+    if !more_logic_for_logic_god(&input) {
+        // We don't have an exact location this time,
+        // so just highlight the proc-macro invocation itself
+        abort_call_site!(
+            "Bad, bad user! Now go stand in the corner and think about what you did!");
+    }
+
+    // Now all the processing is done, return `proc_macro::TokenStream`
+    quote!(/* stuff */).into()
+}
+```
+
+### `proc_macro::Diagnostic`-like usage
+
+```rust
+use proc_macro_error::*;
+use proc_macro::TokenStream;
+use syn::{spanned::Spanned, DeriveInput, ItemStruct, Fields, Attribute , parse_macro_input};
+use quote::quote;
+
+fn process_attrs(attrs: &[Attribute]) -> Vec<Attribute> {
+    attrs
+        .iter()
+        .filter_map(|attr| match process_attr(attr) {
+            Ok(res) => Some(res),
+            Err(msg) => {
+                emit_error!(attr.span(), "Invalid attribute: {}", msg);
+                None
+            }
+        })
+        .collect()
+}
+
+fn process_fields(_attrs: &Fields) -> Vec<TokenStream> {
+    // processing fields in pretty much the same way as attributes
+    unimplemented!()
+}
+
+#[proc_macro]
+#[proc_macro_error]
+pub fn make_answer(input: TokenStream) -> TokenStream {
+    let input = parse_macro_input!(input as ItemStruct);
+    let attrs = process_attrs(&input.attrs);
+
+    // abort right now if some errors were encountered
+    // at the attributes processing stage
+    abort_if_dirty();
+
+    let fields = process_fields(&input.fields);
+
+    // no need to think about emitted errors
+    // #[proc_macro_error] will handle them for you
+    //
+    // just return a TokenStream as you normally would
+    quote!(/* stuff */).into()
+}
+```
+
+## Limitations
+
+- Warnings are emitted only on nightly, they're ignored on stable.
+- "help" suggestions cannot have their own span info on stable, (they inherit parent span).
+- If a panic occurs somewhere in your macro no errors will be displayed. This is not a
+  technical limitation but intentional design, `panic` is not for error reporting.
+
+## MSRV policy
+
+`proc_macro_error` will always be compatible with proc-macro holy trinity:
+`proc_macro2`, `syn`, `quote` crates. In other words, if the trinity is available
+to you than `proc_macro_error` is available too.
+
+## Motivation
+
+Error handling in proc-macros sucks. There's not much of a choice today:
+you either "bubble up" the error up to the top-level of your macro and convert it to
+a [`compile_error!`][compl_err] invocation or just use a good old panic. Both these ways suck:
+
+- Former sucks because it's quite redundant to unroll a proper error handling
+    just for critical errors that will crash the macro anyway so people mostly
+    choose not to bother with it at all and use panic. Almost nobody does it,
+    simple `.expect` is too tempting.
+
+    Also, if you do decide to implement this `Result`-based architecture in your macro
+    you're going to have to rewrite it entirely once [`proc_macro::Diagnostic`][] is finally stable.
+    Not cool.
+
+- Later sucks because there's no way to carry out span info via `panic!`. `rustc` will highlight
+    the whole invocation itself but not some specific token inside it.
+
+    Furthermore, panics aren't for error-reporting at all; panics are for bug-detecting
+    (like unwrapping on `None` or out-of-range indexing) or for early development stages
+    when you need a prototype ASAP and error handling can wait. Mixing these usages only
+    messes things up.
+
+- There is [`proc_macro::Diagnostic`][] which is awesome but it has been experimental
+    for more than a year and is unlikely to be stabilized any time soon.
+
+    This crate's API is intentionally designed to be compatible with `proc_macro::Diagnostic`
+    and delegates to it whenever possible. Once `Diagnostics` is stable this crate
+    will **always** delegate to it, no code changes will be required on user side.
+
+That said, we need a solution, but this solution must meet these conditions:
+
+- It must be better than `panic!`. The main point: it must offer a way to carry span information
+    over to user.
+- It must take as little effort as possible to migrate from `panic!`. Ideally, a new
+    macro with the same semantics plus ability to carry out span info. We should also keep
+    in mind the existence of [`proc_macro::Diagnostic`][] .
+- **It must be usable on stable**.
+
+This crate aims to provide such a mechanism. All you have to do is annotate your top-level
+`#[proc_macro]` function with `#[proc_macro_errors]` attribute and change panics to
+[`abort!`]/[`abort_call_site!`] where appropriate, see [the Guide][guide].
+
+## Disclaimer
+Please note that **this crate is not intended to be used in any way other
+than proc-macro error reporting**, use `Result` and `?` for anything else.
+
+<br>
+
+#### License
+
+<sup>
+Licensed under either of <a href="LICENSE-APACHE">Apache License, Version
+2.0</a> or <a href="LICENSE-MIT">MIT license</a> at your option.
+</sup>
+
+<br>
+
+<sub>
+Unless you explicitly state otherwise, any contribution intentionally submitted
+for inclusion in this crate by you, as defined in the Apache-2.0 license, shall
+be dual licensed as above, without any additional terms or conditions.
+</sub>
+
+
+[compl_err]: https://doc.rust-lang.org/std/macro.compile_error.html
+[`proc_macro::Diagnostic`]: https://doc.rust-lang.org/proc_macro/struct.Diagnostic.html
+
+[crate::dummy]: https://docs.rs/proc-macro-error/0.4/proc_macro_error/dummy/index.html
+[crate::multi]: https://docs.rs/proc-macro-error/0.4/proc_macro_error/multi/index.html
+
+[`abort_call_site!`]: https://docs.rs/proc-macro-error/0.4/proc_macro_error/macro.abort_call_site.html
+[`abort!`]: https://docs.rs/proc-macro-error/0.4/proc_macro_error/macro.abort.html
+[guide]: https://docs.rs/proc-macro-error
diff --git a/proc-macro-error/proc-macro-error-attr/Cargo.toml b/proc-macro-error/proc-macro-error-attr/Cargo.toml
new file mode 100644
index 0000000..6dee68e
--- /dev/null
+++ b/proc-macro-error/proc-macro-error-attr/Cargo.toml
@@ -0,0 +1,18 @@
+[package]
+name = "proc-macro-error-attr"
+version = "0.4.3"
+authors = ["CreepySkeleton <creepy-skeleton@yandex.ru>"]
+edition = "2018"
+description = "attribute macro for proc-macro-error crate"
+license = "MIT OR Apache-2.0"
+repository = "https://gitlab.com/CreepySkeleton/proc-macro-error"
+
+[lib]
+proc-macro = true
+
+[dependencies]
+quote = "1"
+proc-macro2 = "1"
+syn = { version = "1", default-features = false, features = ["derive", "parsing", "proc-macro"] }
+syn-mid = "0.4"
+rustversion = "1.0"
diff --git a/proc-macro-error/proc-macro-error-attr/src/lib.rs b/proc-macro-error/proc-macro-error-attr/src/lib.rs
new file mode 100644
index 0000000..3c1013b
--- /dev/null
+++ b/proc-macro-error/proc-macro-error-attr/src/lib.rs
@@ -0,0 +1,162 @@
+extern crate proc_macro;
+
+use proc_macro::TokenStream;
+use proc_macro2::Ident;
+use quote::quote;
+use std::iter::FromIterator;
+use syn::{
+    parse::{Parse, ParseStream},
+    parse_macro_input,
+    punctuated::Punctuated,
+    Attribute, Token,
+};
+use syn_mid::{Block, ItemFn};
+
+use self::Setting::*;
+
+#[proc_macro_attribute]
+pub fn proc_macro_error(attr: TokenStream, input: TokenStream) -> TokenStream {
+    let input = parse_macro_input!(input as ItemFn);
+    let mut settings = match syn::parse::<Settings>(attr) {
+        Ok(settings) => settings,
+        Err(err) => {
+            let err = err.to_compile_error();
+            return quote!(#input #err).into();
+        }
+    };
+
+    let is_proc_macro = is_proc_macro(&input.attrs);
+    if is_proc_macro {
+        settings.set(AssertUnwindSafe);
+    }
+
+    if detect_proc_macro_hack(&input.attrs) {
+        settings.set(ProcMacroHack);
+    }
+
+    if !(settings.is_set(AllowNotMacro) || is_proc_macro) {
+        return quote!(
+            #input
+            compile_error!("#[proc_macro_error] attribute can be used only with a proc-macro\n\n  \
+                hint: if you are really sure that #[proc_macro_error] should be applied \
+                to this exact function use #[proc_macro_error(allow_not_macro)]\n");
+        )
+        .into();
+    }
+
+    let ItemFn {
+        attrs,
+        vis,
+        constness,
+        asyncness,
+        unsafety,
+        abi,
+        fn_token,
+        ident,
+        generics,
+        inputs,
+        output,
+        block,
+        ..
+    } = input;
+
+    let body = gen_body(block, settings);
+
+    quote!(
+        #(#attrs)*
+        #vis
+        #constness
+        #asyncness
+        #unsafety
+        #abi
+        #fn_token
+        #ident
+        #generics
+        (#inputs)
+        #output
+
+        { #body }
+    )
+    .into()
+}
+
+#[derive(PartialEq)]
+enum Setting {
+    AssertUnwindSafe,
+    AllowNotMacro,
+    ProcMacroHack,
+}
+
+impl Parse for Setting {
+    fn parse(input: ParseStream) -> syn::Result<Self> {
+        let ident: Ident = input.parse()?;
+        match &*ident.to_string() {
+            "assert_unwind_safe" => Ok(AssertUnwindSafe),
+            "allow_not_macro" => Ok(AllowNotMacro),
+            "proc_macro_hack" => Ok(ProcMacroHack),
+            _ => Err(syn::Error::new(
+                ident.span(),
+                format!(
+                    "unknown setting `{}`, expected one of \
+                     `assert_unwind_safe`, `allow_not_macro`, `proc_macro_hack`",
+                    ident
+                ),
+            )),
+        }
+    }
+}
+
+struct Settings(Vec<Setting>);
+impl Parse for Settings {
+    fn parse(input: ParseStream) -> syn::Result<Self> {
+        let punct = Punctuated::<Setting, Token![,]>::parse_terminated(input)?;
+        Ok(Settings(Vec::from_iter(punct)))
+    }
+}
+
+impl Settings {
+    fn is_set(&self, setting: Setting) -> bool {
+        self.0.iter().any(|s| *s == setting)
+    }
+
+    fn set(&mut self, setting: Setting) {
+        self.0.push(setting)
+    }
+}
+
+#[rustversion::since(1.37)]
+fn gen_body(block: Block, settings: Settings) -> proc_macro2::TokenStream {
+    let is_proc_macro_hack = settings.is_set(ProcMacroHack);
+    let closure = if settings.is_set(AssertUnwindSafe) {
+        quote!(::std::panic::AssertUnwindSafe(|| #block ))
+    } else {
+        quote!(|| #block)
+    };
+
+    quote!( ::proc_macro_error::entry_point(#closure, #is_proc_macro_hack) )
+}
+
+// FIXME:
+// proc_macro::TokenStream does not implement UnwindSafe until 1.37.0.
+// Considering this is the closure's return type the unwind safety check would fail
+// for virtually every closure possible, the check is meaningless.
+#[rustversion::before(1.37)]
+fn gen_body(block: Block, settings: Settings) -> proc_macro2::TokenStream {
+    let is_proc_macro_hack = settings.is_set(ProcMacroHack);
+    let closure = quote!(::std::panic::AssertUnwindSafe(|| #block ));
+    quote!( ::proc_macro_error::entry_point(#closure, #is_proc_macro_hack) )
+}
+
+fn detect_proc_macro_hack(attrs: &[Attribute]) -> bool {
+    attrs
+        .iter()
+        .any(|attr| attr.path.is_ident("proc_macro_hack"))
+}
+
+fn is_proc_macro(attrs: &[Attribute]) -> bool {
+    attrs.iter().any(|attr| {
+        attr.path.is_ident("proc_macro")
+            || attr.path.is_ident("proc_macro_derive")
+            || attr.path.is_ident("proc_macro_attribute")
+    })
+}
diff --git a/proc-macro-error/proc-macro-error/Cargo.toml b/proc-macro-error/proc-macro-error/Cargo.toml
new file mode 100644
index 0000000..2da213a
--- /dev/null
+++ b/proc-macro-error/proc-macro-error/Cargo.toml
@@ -0,0 +1,26 @@
+[package]
+name = "proc-macro-error"
+version = "0.4.4"
+authors = ["CreepySkeleton <creepy-skeleton@yandex.ru>"]
+description = "Almost drop-in replacement to panics in proc-macros"
+
+repository = "https://gitlab.com/CreepySkeleton/proc-macro-error"
+readme = "../README.md"
+keywords = ["proc-macro", "error", "errors"]
+categories = ["development-tools::procedural-macro-helpers"]
+license = "MIT OR Apache-2.0"
+
+edition = "2018"
+build = "build.rs"
+
+[badges]
+maintenance = { status = "actively-developed" }
+
+[dependencies]
+quote = "1"
+proc-macro2 = "1"
+syn = { version = "1", default-features = false }
+proc-macro-error-attr = { path = "../proc-macro-error-attr", version = "0.4.3"}
+
+[build-dependencies]
+rustversion = "1.0"
diff --git a/proc-macro-error/proc-macro-error/build.rs b/proc-macro-error/proc-macro-error/build.rs
new file mode 100644
index 0000000..04ddc11
--- /dev/null
+++ b/proc-macro-error/proc-macro-error/build.rs
@@ -0,0 +1,11 @@
+#[rustversion::nightly]
+fn nightly() {
+    println!("cargo:rustc-cfg=pme_nightly");
+}
+
+#[rustversion::not(nightly)]
+fn nightly() {}
+
+fn main() {
+    nightly()
+}
diff --git a/proc-macro-error/proc-macro-error/src/dummy.rs b/proc-macro-error/proc-macro-error/src/dummy.rs
new file mode 100644
index 0000000..f7443b3
--- /dev/null
+++ b/proc-macro-error/proc-macro-error/src/dummy.rs
@@ -0,0 +1,136 @@
+//! Facility to emit dummy implementations (or whatever) in case
+//! an error happen.
+//!
+//! `compile_error!` does not abort a compilation right away. This means
+//! `rustc` doesn't just show you the error and abort, it carries on the
+//! compilation process looking for other errors to report.
+//!
+//! Let's consider an example:
+//!
+//! ```rust,ignore
+//! use proc_macro::TokenStream;
+//! use proc_macro_error::*;
+//!
+//! trait MyTrait {
+//!     fn do_thing();
+//! }
+//!
+//! // this proc macro is supposed to generate MyTrait impl
+//! #[proc_macro_derive(MyTrait)]
+//! #[proc_macro_error]
+//! fn example(input: TokenStream) -> TokenStream {
+//!     // somewhere deep inside
+//!     abort!(span, "something's wrong");
+//!
+//!     // this implementation will be generated if no error happened
+//!     quote! {
+//!         impl MyTrait for #name {
+//!             fn do_thing() {/* whatever */}
+//!         }
+//!     }
+//! }
+//!
+//! // ================
+//! // in main.rs
+//!
+//! // this derive triggers an error
+//! #[derive(MyTrait)] // first BOOM!
+//! struct Foo;
+//!
+//! fn main() {
+//!     Foo::do_thing(); // second BOOM!
+//! }
+//! ```
+//!
+//! The problem is: the generated token stream contains only `compile_error!`
+//! invocation, the impl was not generated. That means user will see two compilation
+//! errors:
+//!
+//! ```text
+//! error: something's wrong
+//!  --> $DIR/probe.rs:9:10
+//!   |
+//! 9 |#[proc_macro_derive(MyTrait)]
+//!   |                    ^^^^^^^
+//!
+//! error[E0599]: no function or associated item named `do_thing` found for type `Foo` in the current scope
+//!  --> src\main.rs:3:10
+//!   |
+//! 1 | struct Foo;
+//!   | ----------- function or associated item `do_thing` not found for this
+//! 2 | fn main() {
+//! 3 |     Foo::do_thing(); // second BOOM!
+//!   |          ^^^^^^^^ function or associated item not found in `Foo`
+//! ```
+//!
+//! But the second error is meaningless! We definitely need to fix this.
+//!
+//! Most used approach in cases like this is "dummy implementation" -
+//! omit `impl MyTrait for #name` and fill functions bodies with `unimplemented!()`.
+//!
+//! This is how you do it:
+//!
+//! ```rust,ignore
+//! use proc_macro::TokenStream;
+//! use proc_macro_error::*;
+//!
+//!  trait MyTrait {
+//!      fn do_thing();
+//!  }
+//!
+//!  // this proc macro is supposed to generate MyTrait impl
+//!  #[proc_macro_derive(MyTrait)]
+//!  #[proc_macro_error]
+//!  fn example(input: TokenStream) -> TokenStream {
+//!      // first of all - we set a dummy impl which will be appended to
+//!      // `compile_error!` invocations in case a trigger does happen
+//!      set_dummy(quote! {
+//!          impl MyTrait for #name {
+//!              fn do_thing() { unimplemented!() }
+//!          }
+//!      });
+//!
+//!      // somewhere deep inside
+//!      abort!(span, "something's wrong");
+//!
+//!      // this implementation will be generated if no error happened
+//!      quote! {
+//!          impl MyTrait for #name {
+//!              fn do_thing() {/* whatever */}
+//!          }
+//!      }
+//!  }
+//!
+//!  // ================
+//!  // in main.rs
+//!
+//!  // this derive triggers an error
+//!  #[derive(MyTrait)] // first BOOM!
+//!  struct Foo;
+//!
+//!  fn main() {
+//!      Foo::do_thing(); // no more errors!
+//!  }
+//! ```
+
+use proc_macro2::TokenStream;
+use std::cell::Cell;
+
+use crate::check_correctness;
+
+thread_local! {
+    static DUMMY_IMPL: Cell<Option<TokenStream>> = Cell::new(None);
+}
+
+/// Sets dummy token stream which will be appended to `compile_error!(msg);...`
+/// invocations in case you'll emit any errors.
+///
+/// See [guide](../index.html#guide).
+pub fn set_dummy(dummy: TokenStream) -> Option<TokenStream> {
+    check_correctness();
+    DUMMY_IMPL.with(|old_dummy| old_dummy.replace(Some(dummy)))
+}
+
+pub(crate) fn cleanup() -> Option<TokenStream> {
+    DUMMY_IMPL.with(|old_dummy| old_dummy.replace(None))
+}
diff --git a/proc-macro-error/proc-macro-error/src/lib.rs b/proc-macro-error/proc-macro-error/src/lib.rs
new file mode 100644
index 0000000..5fb0223
--- /dev/null
+++ b/proc-macro-error/proc-macro-error/src/lib.rs
@@ -0,0 +1,514 @@
+//! # proc-macro-error
+//!
+//! This crate aims to make error reporting in proc-macros simple and easy to use.
+//! Migrate from `panic!`-based errors for as little effort as possible!
+//!
+//! Also, there's ability to [append a dummy token stream](dummy/index.html) to your errors.
+//!
+//! ## Limitations
+//!
+//! - Warnings are emitted only on nightly, they're ignored on stable.
+//! - "help" suggestions cannot have their own span info on stable, (they inherit parent span).
+//! - If a panic occurs somewhere in your macro no errors will be displayed. This is not a
+//!   technical limitation but intentional design, `panic` is not for error reporting.
+//!
+//! ## Guide
+//!
+//! ### Macros
+//!
+//! First of all - **all the emitting-related API must be used within a function
+//! annotated with [`#[proc_macro_error]`](#proc_macro_error-attribute) attribute**. You'll just get a
+//! panic otherwise, no errors will be shown.
+//!
+//! For most of the time you will be using macros.
+//!
+//! - [`abort!`]:
+//!
+//!     Very much panic-like usage - abort execution and show the error. Expands to [`!`] (never type).
+//!
+//! - [`abort_call_site!`]:
+//!
+//!     Shortcut for `abort!(Span::call_site(), ...)`. Expands to [`!`] (never type).
+//!
+//! - [`emit_error!`]:
+//!
+//!     [`proc_macro::Diagnostic`]-like usage - emit the error but do not abort the macro.
+//!     The compilation will fail nonetheless. Expands to [`()`] (unit type).
+//!
+//! - [`emit_call_site_error!`]:
+//!
+//!     Shortcut for `emit_error!(Span::call_site(), ...)`. Expands to [`()`] (unit type).
+//!
+//! - [`emit_warning!`]:
+//!
+//!     Like `emit_error!` but emit a warning instead of error. The compilation won't fail
+//!     because of warnings.
+//!     Expands to [`()`] (unit type).
+//!
+//!     **Beware**: warnings are nightly only, they are completely ignored on stable.
+//!
+//! - [`emit_call_site_warning!`]:
+//!
+//!     Shortcut for `emit_warning!(Span::call_site(), ...)`. Expands to `()` (unit type).
+//!
+//! - [`diagnostic`]:
+//!
+//!     Build instance of `Diagnostic` in format-like style.
+//!
+//! ### Syntax
+//!
+//! All the macros have pretty much the same syntax:
+//!
+//! 1.  ```ignore
+//!     abort!(single_expr)
+//!     ```
+//!     Shortcut for `Diagnostic::from().abort()`
+//!
+//! 2.  ```ignore
+//!     abort!(span, message)
+//!     ```
+//!     Shortcut for `Diagnostic::spanned(span, message.to_string()).abort()`
+//!
+//! 3.  ```ignore
+//!     abort!(span, format_literal, format_args...)
+//!     ```
+//!     Shortcut for `Diagnostic::spanned(span, format!(format_literal, format_args...)).abort()`
+//!
+//! That's it. `abort!`, `emit_warning`, `emit_error` share this exact syntax.
+//! `abort_call_site!`, `emit_call_site_warning`, `emit_call_site_error` lack 1 form
+//! and do not take span in 2 and 3 forms.
+//!
+//! `diagnostic!` require `Level` instance between `span` and second argument (1 form is the same).
+//!
+//! #### Note attachments
+//!
+//! 3.  Every macro can have "note" attachments (only 2 and 3 form).
+//!   ```ignore
+//!   let opt_help = if have_some_info { Some("did you mean `this`?") } else { None };
+//!
+//!   abort!(
+//!       span, message; // <--- attachments start with `;` (semicolon)
+//!
+//!       help = "format {} {}", "arg1", "arg2"; // <--- every attachment ends with `;`,
+//!                                              //      maybe except the last one
+//!
+//!       note = "to_string"; // <--- one arg uses `.to_string()` instead of `format!()`
+//!
+//!       yay = "I see what {} did here", "you"; // <--- "help =" and "hint =" are mapped to Diagnostic::help
+//!                                              //      anything else is Diagnostic::note
+//!
+//!       wow = note_span => "custom span"; // <--- attachments can have their own span
+//!                                         //      it takes effect only on nightly though
+//!
+//!       hint =? opt_help; // <-- "optional" attachment, get displayed only if `Some`
+//!                         //     must be single `Option` expression
+//!
+//!       note =? note_span => opt_help // <-- optional attachments can have custom spans too
+//!   )
+//!   ```
+//!
+//! ### `#[proc_macro_error]` attribute
+//!
+//! **This attribute MUST be present on the top level of your macro.**
+//!
+//! This attribute performs the setup and cleanup necessary to make things work.
+//!
+//! #### Syntax
+//!
+//! `#[proc_macro_error]` or `#[proc_macro_error(settings...)]`, where `settings...`
+//! is a comma-separated list of:
+//!
+//! - `proc_macro_hack`:
+//!
+//!     To correctly cooperate with `#[proc_macro_hack]` `#[proc_macro_error]`
+//!     attribute must be placed *before* (above) it, like this:
+//!
+//!     ```ignore
+//!     #[proc_macro_error]
+//!     #[proc_macro_hack]
+//!     #[proc_macro]
+//!     fn my_macro(input: TokenStream) -> TokenStream {
+//!         unimplemented!()
+//!     }
+//!     ```
+//!
+//!     If, for some reason, you can't place it like that you can use
+//!     `#[proc_macro_error(proc_macro_hack)]` instead.
+//!
+//! - `allow_not_macro`:
+//!
+//!     By default, the attribute checks that it's applied to a proc-macro.
+//!     If none of `#[proc_macro]`, `#[proc_macro_derive]` nor `#[proc_macro_attribute]` are
+//!     present it will panic. It's the intention - this crate is supposed to be used only with
+//!     proc-macros. This setting is made to bypass the check, useful in certain
+//!     circumstances.
+//!
+//!     Please note: the function this attribute is applied to must return `proc_macro::TokenStream`.
+//!
+//! - `assert_unwind_safe`:
+//!
+//!     By default, your code must be [unwind safe]. If your code is not unwind safe but you believe
+//!     it's correct you can use this setting to bypass the check. This is typically needed
+//!     for code that uses `lazy_static` or `thread_local` with `Cell/RefCell` inside.
+//!
+//!     This setting is implied if `#[proc_macro_error]` is applied to a function
+//!     marked as `#[proc_macro]`, `#[proc_macro_derive]` or `#[proc_macro_attribute]`.
+//!
+//! ### Diagnostic type
+//!
+//! [`Diagnostic`] type is intentionally designed to be API compatible with [`proc_macro::Diagnostic`].
+//! Not all API is implemented, only the part that can be reasonably implemented on stable.
+//!
+//!
+//! [`abort!`]: macro.abort.html
+//! [`emit_warning!`]: macro.emit_warning.html
+//! [`emit_error!`]: macro.emit_error.html
+//! [`abort_call_site!`]: macro.abort_call_site.html
+//! [`emit_call_site_warning!`]: macro.emit_call_site_error.html
+//! [`emit_call_site_error!`]: macro.emit_call_site_warning.html
+//! [`diagnostic!`]: macro.diagnostic.html
+//! [proc_macro_error]: ./../proc_macro_error_attr/attr.proc_macro_error.html
+//! [`Diagnostic`]: struct.Diagnostic.html
+//! [`proc_macro::Diagnostic`]: https://doc.rust-lang.org/proc_macro/struct.Diagnostic.html
+//! [unwind safe]: https://doc.rust-lang.org/std/panic/trait.UnwindSafe.html#what-is-unwind-safety
+//! [`!`]: https://doc.rust-lang.org/std/primitive.never.html
+//! [`()`]: https://doc.rust-lang.org/std/primitive.unit.html
+
+#![cfg_attr(pme_nightly, feature(proc_macro_diagnostic))]
+#![forbid(unsafe_code)]
+
+// reexports for use in macros
+#[doc(hidden)]
+pub extern crate proc_macro;
+#[doc(hidden)]
+pub extern crate proc_macro2;
+
+pub use self::dummy::set_dummy;
+pub use proc_macro_error_attr::proc_macro_error;
+
+use proc_macro2::{Span, TokenStream};
+use quote::quote;
+use quote::{quote_spanned, ToTokens};
+use std::cell::Cell;
+use std::panic::{catch_unwind, resume_unwind, UnwindSafe};
+
+pub mod dummy;
+
+mod macros;
+
+#[cfg(not(any(pme_nightly, nightly_fmt)))]
+#[path = "stable.rs"]
+mod imp;
+
+#[cfg(any(pme_nightly, nightly_fmt))]
+#[path = "nightly.rs"]
+mod imp;
+
+/// Represents a diagnostic level
+///
+/// # Warnings
+///
+/// Warnings are ignored on stable/beta
+#[derive(Debug, PartialEq)]
+pub enum Level {
+    Error,
+    Warning,
+    #[doc(hidden)]
+    NonExhaustive,
+}
+
+/// Represents a single diagnostic message
+#[derive(Debug)]
+pub struct Diagnostic {
+    level: Level,
+    span: Span,
+    msg: String,
+    suggestions: Vec<(SuggestionKind, String, Option<Span>)>,
+}
+
+/// This traits expands `Result<T, Into<Diagnostic>>` with some handy shortcuts.
+pub trait ResultExt {
+    type Ok;
+
+    /// Behaves like `Result::unwrap`: if self is `Ok` yield the contained value,
+    /// otherwise abort macro execution via `abort!`.
+    fn unwrap_or_abort(self) -> Self::Ok;
+
+    /// Behaves like `Result::expect`: if self is `Ok` yield the contained value,
+    /// otherwise abort macro execution via `abort!`.
+    /// If it aborts then resulting error message will be preceded with `message`.
+    fn expect_or_abort(self, msg: &str) -> Self::Ok;
+}
+
+/// This traits expands `Option` with some handy shortcuts.
+pub trait OptionExt {
+    type Some;
+
+    /// Behaves like `Option::expect`: if self is `Some` yield the contained value,
+    /// otherwise abort macro execution via `abort_call_site!`.
+    /// If it aborts the `message` will be used for [`compile_error!`][compl_err] invocation.
+    ///
+    /// [compl_err]: https://doc.rust-lang.org/std/macro.compile_error.html
+    fn expect_or_abort(self, msg: &str) -> Self::Some;
+}
+
+impl Diagnostic {
+    /// Create a new diagnostic message that points to `Span::call_site()`
+    pub fn new(level: Level, message: String) -> Self {
+        Diagnostic::spanned(Span::call_site(), level, message)
+    }
+
+    /// Create a new diagnostic message that points to the `span`
+    pub fn spanned(span: Span, level: Level, message: String) -> Self {
+        Diagnostic {
+            level,
+            span,
+            msg: message,
+            suggestions: vec![],
+        }
+    }
+
+    /// Attach a "help" note to your main message, note will have it's own span on nightly.
+    ///
+    /// # Span
+    ///
+    /// The span is ignored on stable, the note effectively inherits its parent's (main message) span
+    pub fn span_help(mut self, span: Span, msg: String) -> Self {
+        self.suggestions
+            .push((SuggestionKind::Help, msg, Some(span)));
+        self
+    }
+
+    /// Attach a "help" note to your main message,
+    pub fn help(mut self, msg: String) -> Self {
+        self.suggestions.push((SuggestionKind::Help, msg, None));
+        self
+    }
+
+    /// Attach a note to your main message, note will have it's own span on nightly.
+    ///
+    /// # Span
+    ///
+    /// The span is ignored on stable, the note effectively inherits its parent's (main message) span
+    pub fn span_note(mut self, span: Span, msg: String) -> Self {
+        self.suggestions
+            .push((SuggestionKind::Note, msg, Some(span)));
+        self
+    }
+
+    /// Attach a note to your main message
+    pub fn note(mut self, msg: String) -> Self {
+        self.suggestions.push((SuggestionKind::Note, msg, None));
+        self
+    }
+
+    /// The message of main warning/error (no notes attached)
+    pub fn message(&self) -> &str {
+        &self.msg
+    }
+
+    /// Abort the proc-macro's execution and display the diagnostic.
+    ///
+    /// # Warnings
+    ///
+    /// Warnings do not get emitted on stable/beta but this function will abort anyway.
+    pub fn abort(self) -> ! {
+        self.emit();
+        abort_now()
+    }
+
+    /// Display the diagnostic while not aborting macro execution.
+    ///
+    /// # Warnings
+    ///
+    /// Warnings are ignored on stable/beta
+    pub fn emit(self) {
+        imp::emit_diagnostic(self);
+    }
+}
+
+/// Abort macro execution and display all the emitted errors, if any.
+///
+/// Does nothing if no errors were emitted (warnings do not count).
+pub fn abort_if_dirty() {
+    imp::abort_if_dirty();
+}
+
+#[doc(hidden)]
+impl Diagnostic {
+    pub fn span_suggestion(self, span: Span, suggestion: &str, msg: String) -> Self {
+        match suggestion {
+            "help" | "hint" => self.span_help(span, msg),
+            _ => self.span_note(span, msg),
+        }
+    }
+
+    pub fn suggestion(self, suggestion: &str, msg: String) -> Self {
+        match suggestion {
+            "help" | "hint" => self.help(msg),
+            _ => self.note(msg),
+        }
+    }
+}
+
+impl ToTokens for Diagnostic {
+    fn to_tokens(&self, ts: &mut TokenStream) {
+        use std::borrow::Cow;
+
+        fn ensure_lf(buf: &mut String, s: &str) {
+            if s.ends_with('\n') {
+                buf.push_str(s);
+            } else {
+                buf.push_str(s);
+                buf.push('\n');
+            }
+        }
+
+        let Diagnostic {
+            ref msg,
+            ref suggestions,
+            ref level,
+            ..
+        } = *self;
+
+        if *level == Level::Warning {
+            return;
+        }
+
+        let message = if suggestions.is_empty() {
+            Cow::Borrowed(msg)
+        } else {
+            let mut message = String::new();
+            ensure_lf(&mut message, msg);
+            message.push('\n');
+
+            for (kind, note, _span) in suggestions {
+                message.push_str("  = ");
+                message.push_str(kind.name());
+                message.push_str(": ");
+                ensure_lf(&mut message, note);
+            }
+            message.push('\n');
+
+            Cow::Owned(message)
+        };
+
+        let span = &self.span;
+        let msg = syn::LitStr::new(&*message, *span);
+        ts.extend(quote_spanned!(*span=> compile_error!(#msg); ));
+    }
+}
+
+impl<T, E: Into<Diagnostic>> ResultExt for Result<T, E> {
+    type Ok = T;
+
+    fn unwrap_or_abort(self) -> T {
+        match self {
+            Ok(res) => res,
+            Err(e) => e.into().abort(),
+        }
+    }
+
+    fn expect_or_abort(self, message: &str) -> T {
+        match self {
+            Ok(res) => res,
+            Err(e) => {
+                let mut e = e.into();
+                e.msg = format!("{}: {}", message, e.msg);
+                e.abort()
+            }
+        }
+    }
+}
+
+impl<T> OptionExt for Option<T> {
+    type Some = T;
+
+    fn expect_or_abort(self, message: &str) -> T {
+        match self {
+            Some(res) => res,
+            None => abort_call_site!(message),
+        }
+    }
+}
+
+#[derive(Debug)]
+enum SuggestionKind {
+    Help,
+    Note,
+}
+
+impl SuggestionKind {
+    fn name(&self) -> &'static str {
+        match self {
+            SuggestionKind::Note => "note",
+            SuggestionKind::Help => "help",
+        }
+    }
+}
+
+impl From<syn::Error> for Diagnostic {
+    fn from(e: syn::Error) -> Self {
+        Diagnostic::spanned(e.span(), Level::Error, e.to_string())
+    }
+}
+
+/// This is the entry point for a proc-macro.
+///
+/// **NOT PUBLIC API, SUBJECT TO CHANGE WITHOUT ANY NOTICE**
+#[doc(hidden)]
+pub fn entry_point<F>(f: F, proc_macro_hack: bool) -> proc_macro::TokenStream
+where
+    F: FnOnce() -> proc_macro::TokenStream + UnwindSafe,
+{
+    ENTERED_ENTRY_POINT.with(|flag| flag.set(true));
+    let caught = catch_unwind(f);
+    let dummy = dummy::cleanup();
+    let err_storage = imp::cleanup();
+    ENTERED_ENTRY_POINT.with(|flag| flag.set(false));
+
+    let mut appendix = TokenStream::new();
+    if proc_macro_hack {
+        appendix.extend(quote! {
+            #[allow(unused)]
+            macro_rules! proc_macro_call {
+                () => ( unimplemented!() )
+            }
+        });
+    }
+
+    match caught {
+        Ok(ts) => {
+            if err_storage.is_empty() {
+                ts
+            } else {
+                quote!( #(#err_storage)* #dummy #appendix ).into()
+            }
+        }
+
+        Err(boxed) => match boxed.downcast::<AbortNow>() {
+            Ok(_) => quote!( #(#err_storage)* #dummy #appendix ).into(),
+            Err(boxed) => resume_unwind(boxed),
+        },
+    }
+}
+
+fn abort_now() -> ! {
+    check_correctness();
+    panic!(AbortNow)
+}
+
+thread_local! {
+    static ENTERED_ENTRY_POINT: Cell<bool> = Cell::new(false);
+}
+
+struct AbortNow;
+
+fn check_correctness() {
+    if !ENTERED_ENTRY_POINT.with(|flag| flag.get()) {
+        panic!(
+            "proc-macro-error API cannot be used outside of `entry_point` invocation, \
+             perhaps you forgot to annotate your #[proc_macro] function with `#[proc_macro_error]"
+        );
+    }
+}
diff --git a/proc-macro-error/proc-macro-error/src/macros.rs b/proc-macro-error/proc-macro-error/src/macros.rs
new file mode 100644
index 0000000..117612c
--- /dev/null
+++ b/proc-macro-error/proc-macro-error/src/macros.rs
@@ -0,0 +1,257 @@
+// FIXME: this can be greatly simplified via $()?
+// as soon as MRSV hits 1.32
+
+/// Build [`Diagnostic`](struct.Diagnostic.html) instance from provided arguments.
+///
+/// # Syntax
+///
+/// See [the guide](index.html#guide).
+///
+#[macro_export]
+macro_rules! diagnostic {
+    // from alias
+    ($err:expr) => { $crate::Diagnostic::from($err) };
+
+    // span, message, help
+    ($span:expr, $level:expr, $fmt:expr, $($args:expr),+ ; $($rest:tt)+) => {{
+        let diag = $crate::Diagnostic::spanned(
+            $span.into(),
+            $level,
+            format!($fmt, $($args),*)
+        );
+        $crate::__pme__suggestions!(diag $($rest)*);
+        diag
+    }};
+
+    ($span:expr, $level:expr, $msg:expr ; $($rest:tt)+) => {{
+        let diag = $crate::Diagnostic::spanned($span.into(), $level, $msg.to_string());
+        $crate::__pme__suggestions!(diag $($rest)*);
+        diag
+    }};
+
+    // span, message, no help
+    ($span:expr, $level:expr, $fmt:expr, $($args:expr),+) => {{
+        $crate::Diagnostic::spanned(
+            $span.into(),
+            $level,
+            format!($fmt, $($args),*)
+        )
+    }};
+
+    ($span:expr, $level:expr, $msg:expr) => {{
+        $crate::Diagnostic::spanned($span.into(), $level, $msg.to_string())
+    }};
+
+
+    // trailing commas
+
+    ($span:expr, $level:expr, $fmt:expr, $($args:expr),+, ; $($rest:tt)+) => {
+        $crate::diagnostic!($span, $level, $fmt, $($args),* ; $($rest)*)
+    };
+    ($span:expr, $level:expr, $msg:expr, ; $($rest:tt)+) => {
+        $crate::diagnostic!($span, $level, $msg ; $($rest)*)
+    };
+    ($span:expr, $level:expr, $fmt:expr, $($args:expr),+,) => {
+        $crate::diagnostic!($span, $level, $fmt, $($args),*)
+    };
+    ($span:expr, $level:expr, $msg:expr,) => {
+        $crate::diagnostic!($span, $level, $msg)
+    };
+    // ($err:expr,) => { $crate::diagnostic!($err) };
+}
+
+/// Abort proc-macro execution right now and display the error.
+///
+/// # Syntax
+///
+/// See [the guide](index.html#guide).
+#[macro_export]
+macro_rules! abort {
+    ($err:expr) => {
+        $crate::diagnostic!($err).abort()
+    };
+
+    ($span:expr, $($tts:tt)*) => {
+        $crate::diagnostic!($span, $crate::Level::Error, $($tts)*).abort()
+    };
+}
+
+/// Shortcut for `abort!(Span::call_site(), msg...)`. This macro
+/// is still preferable over plain panic, panics are not for error reporting.
+///
+/// # Syntax
+///
+/// See [the guide](index.html#guide).
+///
+#[macro_export]
+macro_rules! abort_call_site {
+    ($($tts:tt)*) => {
+        $crate::diagnostic!(
+            $crate::proc_macro2::Span::call_site(),
+            $crate::Level::Error,
+            $($tts)*
+        ).abort()
+    };
+}
+
+/// Emit an error while not aborting the proc-macro right away.
+///
+/// # Syntax
+///
+/// See [the guide](index.html#guide).
+///
+#[macro_export]
+macro_rules! emit_error {
+    ($err:expr) => {
+        $crate::diagnostic!($err).emit()
+    };
+
+    ($span:expr, $($tts:tt)*) => {{
+        let level = $crate::Level::Error;
+        $crate::diagnostic!($span, level, $($tts)*).emit()
+    }};
+}
+
+/// Shortcut for `emit_error!(Span::call_site(), ...)`. This macro
+/// is still preferable over plain panic, panics are not for error reporting..
+///
+/// # Syntax
+///
+/// See [the guide](index.html#guide).
+///
+#[macro_export]
+macro_rules! emit_call_site_error {
+    ($($tts:tt)*) => {
+        $crate::diagnostic!(
+            $crate::proc_macro2::Span()::call_site(),
+            $crate::Level::Error,
+            $($tts)*
+        ).emit()
+    };
+}
+
+/// Emit a warning. Warnings are not errors and compilation won't fail because of them.
+///
+/// **Does nothing on stable**
+///
+/// # Syntax
+///
+/// See [the guide](index.html#guide).
+///
+#[macro_export]
+macro_rules! emit_warning {
+    ($span:expr, $($tts:tt)*) => {
+        $crate::diagnostic!($span, $crate::Level::Warning, $($tts)*).emit()
+    };
+}
+
+/// Shortcut for `emit_warning!(Span::call_site(), ...)`.
+///
+/// **Does nothing on stable**
+///
+/// # Syntax
+///
+/// See [the guide](index.html#guide).
+///
+#[macro_export]
+macro_rules! emit_call_site_warning {
+    ($($tts:tt)*) => {{
+        let span = $crate::proc_macro2::Span()::call_site();
+        $crate::diagnostic!(span, $crate::Level::Warning, $($tts)*).emit()
+    }};
+}
+
+#[doc(hidden)]
+#[macro_export]
+macro_rules! __pme__suggestions {
+    ($var:ident) => ();
+
+    ($var:ident $help:ident =? $msg:expr) => {
+        let $var = if let Some(msg) = $msg {
+            $var.suggestion(stringify!($help), msg.to_string())
+        } else {
+            $var
+        };
+    };
+    ($var:ident $help:ident =? $span:expr => $msg:expr) => {
+        let $var = if let Some(msg) = $msg {
+            $var.span_suggestion($span.into(), stringify!($help), msg.to_string())
+        } else {
+            $var
+        };
+    };
+
+    ($var:ident $help:ident =? $msg:expr ; $($rest:tt)*) => {
+        $crate::__pme__suggestions!($var $help =? $msg);
+        $crate::__pme__suggestions!($var $($rest)*);
+    };
+    ($var:ident $help:ident =? $span:expr => $msg:expr ; $($rest:tt)*) => {
+        $crate::__pme__suggestions!($var $help =? $span => $msg);
+        $crate::__pme__suggestions!($var $($rest)*);
+    };
+
+
+    ($var:ident $help:ident = $msg:expr) => {
+        let $var = $var.suggestion(stringify!($help), $msg.to_string());
+    };
+    ($var:ident $help:ident = $fmt:expr, $($args:expr),+) => {
+        let $var = $var.suggestion(
+            stringify!($help),
+            format!($fmt, $($args),*)
+        );
+    };
+    ($var:ident $help:ident = $span:expr => $msg:expr) => {
+        let $var = $var.span_suggestion($span.into(), stringify!($help), $msg.to_string());
+    };
+    ($var:ident $help:ident = $span:expr => $fmt:expr, $($args:expr),+) => {
+        let $var = $var.span_suggestion(
+            $span.into(),
+            stringify!($help),
+            format!($fmt, $($args),*)
+        );
+    };
+
+    ($var:ident $help:ident = $msg:expr ; $($rest:tt)*) => {
+        $crate::__pme__suggestions!($var $help = $msg);
+        $crate::__pme__suggestions!($var $($rest)*);
+    };
+    ($var:ident $help:ident = $fmt:expr, $($args:expr),+ ; $($rest:tt)*) => {
+        $crate::__pme__suggestions!($var $help = $fmt, $($args),*);
+        $crate::__pme__suggestions!($var $($rest)*);
+    };
+    ($var:ident $help:ident = $span:expr => $msg:expr ; $($rest:tt)*) => {
+        $crate::__pme__suggestions!($var $help = $span => $msg);
+        $crate::__pme__suggestions!($var $($rest)*);
+    };
+    ($var:ident $help:ident = $span:expr => $fmt:expr, $($args:expr),+ ; $($rest:tt)*) => {
+        $crate::__pme__suggestions!($var $help = $span => $fmt, $($args),*);
+        $crate::__pme__suggestions!($var $($rest)*);
+    };
+
+    // trailing commas
+
+    ($var:ident $help:ident = $msg:expr,) => {
+        $crate::__pme__suggestions!($var $help = $msg)
+    };
+    ($var:ident $help:ident = $fmt:expr, $($args:expr),+,) => {
+        $crate::__pme__suggestions!($var $help = $fmt, $($args)*)
+    };
+    ($var:ident $help:ident = $span:expr => $msg:expr,) => {
+        $crate::__pme__suggestions!($var $help = $span => $msg)
+    };
+    ($var:ident $help:ident = $span:expr => $fmt:expr, $($args:expr),*,) => {
+        $crate::__pme__suggestions!($var $help = $span => $fmt, $($args)*)
+    };
+    ($var:ident $help:ident = $msg:expr, ; $($rest:tt)*) => {
+        $crate::__pme__suggestions!($var $help = $msg; $($rest)*)
+    };
+    ($var:ident $help:ident = $fmt:expr, $($args:expr),+, ; $($rest:tt)*) => {
+        $crate::__pme__suggestions!($var $help = $fmt, $($args),*; $($rest)*)
+    };
+    ($var:ident $help:ident = $span:expr => $msg:expr, ; $($rest:tt)*) => {
+        $crate::__pme__suggestions!($var $help = $span => $msg; $($rest)*)
+    };
+    ($var:ident $help:ident = $span:expr => $fmt:expr, $($args:expr),+, ; $($rest:tt)*) => {
+        $crate::__pme__suggestions!($var $help = $span => $fmt, $($args),*; $($rest)*)
+    };
+}
diff --git a/proc-macro-error/proc-macro-error/src/nightly.rs b/proc-macro-error/proc-macro-error/src/nightly.rs
new file mode 100644
index 0000000..d053c2f
--- /dev/null
+++ b/proc-macro-error/proc-macro-error/src/nightly.rs
@@ -0,0 +1,49 @@
+use std::sync::atomic::{AtomicBool, Ordering};
+
+use proc_macro::{Diagnostic as PDiag, Level as PLevel};
+
+use crate::{abort_now, check_correctness, Diagnostic, Level, SuggestionKind};
+
+pub fn abort_if_dirty() {
+    check_correctness();
+    if IS_DIRTY.load(Ordering::SeqCst) {
+        abort_now()
+    }
+}
+
+pub(crate) fn cleanup() -> Vec<Diagnostic> {
+    vec![]
+}
+
+pub(crate) fn emit_diagnostic(diag: Diagnostic) {
+    let Diagnostic {
+        level,
+        span,
+        msg,
+        suggestions,
+    } = diag;
+
+    let level = match level {
+        Level::Warning => PLevel::Warning,
+        Level::Error => {
+            IS_DIRTY.store(true, Ordering::SeqCst);
+            PLevel::Error
+        }
+        _ => unreachable!(),
+    };
+
+    let mut res = PDiag::spanned(span.unwrap(), level, msg);
+
+    for (kind, msg, span) in suggestions {
+        res = match (kind, span) {
+            (SuggestionKind::Note, Some(span)) => res.span_note(span.unwrap(), msg),
+            (SuggestionKind::Help, Some(span)) => res.span_help(span.unwrap(), msg),
+            (SuggestionKind::Note, None) => res.note(msg),
+            (SuggestionKind::Help, None) => res.help(msg),
+        }
+    }
+
+    res.emit()
+}
+
+static IS_DIRTY: AtomicBool = AtomicBool::new(false);
diff --git a/proc-macro-error/proc-macro-error/src/stable.rs b/proc-macro-error/proc-macro-error/src/stable.rs
new file mode 100644
index 0000000..07042d3
--- /dev/null
+++ b/proc-macro-error/proc-macro-error/src/stable.rs
@@ -0,0 +1,26 @@
+use std::cell::RefCell;
+
+use crate::{abort_now, check_correctness, Diagnostic, Level};
+
+pub fn abort_if_dirty() {
+    check_correctness();
+    ERR_STORAGE.with(|storage| {
+        if !storage.borrow().is_empty() {
+            abort_now()
+        }
+    });
+}
+
+pub(crate) fn cleanup() -> Vec<Diagnostic> {
+    ERR_STORAGE.with(|storage| storage.replace(Vec::new()))
+}
+
+pub(crate) fn emit_diagnostic(diag: Diagnostic) {
+    if diag.level == Level::Error {
+        ERR_STORAGE.with(|storage| storage.borrow_mut().push(diag));
+    }
+}
+
+thread_local! {
+    static ERR_STORAGE: RefCell<Vec<Diagnostic>> = RefCell::new(Vec::new());
+}
diff --git a/proc-macro-error/test-crate/Cargo.toml b/proc-macro-error/test-crate/Cargo.toml
new file mode 100644
index 0000000..96dadc3
--- /dev/null
+++ b/proc-macro-error/test-crate/Cargo.toml
@@ -0,0 +1,20 @@
+[package]
+name = "test-crate"
+version = "0.0.0"
+authors = ["CreepySkeleton <creepy-skeleton@yandex.ru>"]
+edition = "2018"
+publish = false
+
+[lib]
+proc-macro = true
+
+[dependencies]
+proc-macro-error = { path = "../proc-macro-error"}
+quote = "1"
+proc-macro2 = "1"
+syn = {version = "1", default-features = false }
+
+[dev-dependencies]
+trybuild = "1.0"
+rustversion = "1.0"
+toml = "=0.5.2" # DO NOT BUMP
diff --git a/proc-macro-error/test-crate/src/lib.rs b/proc-macro-error/test-crate/src/lib.rs
new file mode 100644
index 0000000..2ea9175
--- /dev/null
+++ b/proc-macro-error/test-crate/src/lib.rs
@@ -0,0 +1,123 @@
+#[macro_use]
+extern crate proc_macro_error;
+#[macro_use]
+extern crate syn;
+extern crate proc_macro;
+
+use proc_macro2::Span;
+use proc_macro_error::{set_dummy, Level, OptionExt, ResultExt};
+use syn::{
+    parse::{Parse, ParseStream},
+    punctuated::Punctuated,
+    spanned::Spanned,
+    Ident,
+};
+
+struct IdentOrUnderscore {
+    span: Span,
+    part: String,
+}
+
+impl IdentOrUnderscore {
+    fn new(span: Span, part: String) -> Self {
+        IdentOrUnderscore { span, part }
+    }
+}
+
+impl Parse for IdentOrUnderscore {
+    fn parse(input: ParseStream) -> syn::Result<Self> {
+        let la = input.lookahead1();
+
+        if la.peek(Ident) {
+            let t = input.parse::<Ident>().unwrap();
+            Ok(IdentOrUnderscore::new(t.span(), t.to_string()))
+        } else if la.peek(Token![_]) {
+            let t = input.parse::<Token![_]>().unwrap();
+            Ok(IdentOrUnderscore::new(t.span(), "_".to_string()))
+        } else {
+            Err(la.error())
+        }
+    }
+}
+
+struct Args(Vec<IdentOrUnderscore>);
+
+impl Parse for Args {
+    fn parse(input: ParseStream) -> syn::Result<Self> {
+        let args = Punctuated::<_, Token![,]>::parse_terminated(input)?;
+        Ok(Args(args.into_iter().collect()))
+    }
+}
+
+#[proc_macro]
+#[proc_macro_error]
+pub fn make_fn(input: proc_macro::TokenStream) -> proc_macro::TokenStream {
+    let mut name = String::new();
+    let input = parse_macro_input!(input as Args);
+
+    for arg in input.0 {
+        match &*arg.part {
+            "abort" => abort!(
+                arg.span,
+                "abort! 3{} args {}", "+", "test";
+                hint = "help {} test", "message"
+            ),
+
+            "abort_call_site" => abort_call_site!(
+                "abort_call_site! 2{} args {}", "+", "test";
+                help = "help {} test", "message"
+            ),
+
+            "direct_abort" => {
+                diagnostic!(arg.span, Level::Error, "direct MacroError::abort() test").abort()
+            }
+
+            "result_expect" => {
+                let e = syn::Error::new(arg.span, "error");
+                Err(e).expect_or_abort("Result::expect_or_abort() test")
+            }
+
+            "result_unwrap" => {
+                let e = syn::Error::new(arg.span, "Result::unwrap_or_abort() test");
+                Err(e).unwrap_or_abort()
+            }
+
+            "option_expect" => None.expect_or_abort("Option::expect_or_abort() test"),
+
+            "need_default" => {
+                set_dummy(quote! {
+                    impl Default for NeedDefault {
+                        fn default() -> Self {
+                            NeedDefault::A
+                        }
+                    }
+                });
+
+                abort!(arg.span, "set_dummy test")
+            }
+
+            part if part.starts_with("multi") => {
+                let no_help: Option<String> = Option::None;
+                let help = Some("Option help test");
+                emit_error!(
+                    arg.span,
+                    "multiple error part: {}", part;
+                    note = "help {} test", "message";
+                    hint =? help;
+                    wow = "I see what you did here...";
+                    help =? no_help
+                )
+            }
+
+            _ => name.push_str(&arg.part),
+        }
+    }
+
+    // test that unrelated panics are not affected
+    if name.is_empty() {
+        panic!("unrelated panic test")
+    }
+
+    let name = Ident::new(&name, Span::call_site());
+    quote!( fn #name() {} ).into()
+}
diff --git a/proc-macro-error/test-crate/tests/macro-errors.rs b/proc-macro-error/test-crate/tests/macro-errors.rs
new file mode 100644
index 0000000..8c672eb
--- /dev/null
+++ b/proc-macro-error/test-crate/tests/macro-errors.rs
@@ -0,0 +1,6 @@
+#[rustversion::attr(any(not(stable), before(1.39)), ignore)]
+#[test]
+fn ui() {
+    let t = trybuild::TestCases::new();
+    t.compile_fail("tests/ui/*.rs");
+}
diff --git a/proc-macro-error/test-crate/tests/ok.rs b/proc-macro-error/test-crate/tests/ok.rs
new file mode 100644
index 0000000..9b6a3d1
--- /dev/null
+++ b/proc-macro-error/test-crate/tests/ok.rs
@@ -0,0 +1,9 @@
+extern crate test_crate;
+
+use test_crate::make_fn;
+
+make_fn!(it, _, works);
+
+fn main() {
+    it_works();
+}
diff --git a/proc-macro-error/test-crate/tests/ui/abort.rs b/proc-macro-error/test-crate/tests/ui/abort.rs
new file mode 100644
index 0000000..717d772
--- /dev/null
+++ b/proc-macro-error/test-crate/tests/ui/abort.rs
@@ -0,0 +1,6 @@
+extern crate test_crate;
+use test_crate::make_fn;
+
+make_fn!(abort);
+
+fn main() {}
diff --git a/proc-macro-error/test-crate/tests/ui/abort.stderr b/proc-macro-error/test-crate/tests/ui/abort.stderr
new file mode 100644
index 0000000..7c4e6a0
--- /dev/null
+++ b/proc-macro-error/test-crate/tests/ui/abort.stderr
@@ -0,0 +1,8 @@
+error: abort! 3+ args test
+
+  = help: help message test
+
+ --> $DIR/abort.rs:4:10
+  |
+4 | make_fn!(abort);
+  |          ^^^^^
diff --git a/proc-macro-error/test-crate/tests/ui/call_site.rs b/proc-macro-error/test-crate/tests/ui/call_site.rs
new file mode 100644
index 0000000..7184cc4
--- /dev/null
+++ b/proc-macro-error/test-crate/tests/ui/call_site.rs
@@ -0,0 +1,6 @@
+extern crate test_crate;
+use test_crate::make_fn;
+
+make_fn!(abort_call_site);
+
+fn main() {}
diff --git a/proc-macro-error/test-crate/tests/ui/call_site.stderr b/proc-macro-error/test-crate/tests/ui/call_site.stderr
new file mode 100644
index 0000000..d630a3a
--- /dev/null
+++ b/proc-macro-error/test-crate/tests/ui/call_site.stderr
@@ -0,0 +1,8 @@
+error: abort_call_site! 2+ args test
+
+  = help: help message test
+
+ --> $DIR/call_site.rs:4:1
+  |
+4 | make_fn!(abort_call_site);
+  | ^^^^^^^^^^^^^^^^^^^^^^^^^^ in this macro invocation
diff --git a/proc-macro-error/test-crate/tests/ui/direct_abort.rs b/proc-macro-error/test-crate/tests/ui/direct_abort.rs
new file mode 100644
index 0000000..b5a4c97
--- /dev/null
+++ b/proc-macro-error/test-crate/tests/ui/direct_abort.rs
@@ -0,0 +1,6 @@
+extern crate test_crate;
+use test_crate::make_fn;
+
+make_fn!(direct_abort);
+
+fn main() {}
diff --git a/proc-macro-error/test-crate/tests/ui/direct_abort.stderr b/proc-macro-error/test-crate/tests/ui/direct_abort.stderr
new file mode 100644
index 0000000..7cfbae8
--- /dev/null
+++ b/proc-macro-error/test-crate/tests/ui/direct_abort.stderr
@@ -0,0 +1,5 @@
+error: direct MacroError::abort() test
+ --> $DIR/direct_abort.rs:4:10
+  |
+4 | make_fn!(direct_abort);
+  |          ^^^^^^^^^^^^
diff --git a/proc-macro-error/test-crate/tests/ui/dummy.rs b/proc-macro-error/test-crate/tests/ui/dummy.rs
new file mode 100644
index 0000000..7514fe0
--- /dev/null
+++ b/proc-macro-error/test-crate/tests/ui/dummy.rs
@@ -0,0 +1,16 @@
+extern crate test_crate;
+use test_crate::make_fn;
+
+enum NeedDefault {
+    A,
+    B
+}
+
+make_fn!(need_default);
+
+fn main() {
+    let _ = NeedDefault::default();
+}
+
+
+
diff --git a/proc-macro-error/test-crate/tests/ui/dummy.stderr b/proc-macro-error/test-crate/tests/ui/dummy.stderr
new file mode 100644
index 0000000..fd531be
--- /dev/null
+++ b/proc-macro-error/test-crate/tests/ui/dummy.stderr
@@ -0,0 +1,5 @@
+error: set_dummy test
+ --> $DIR/dummy.rs:9:10
+  |
+9 | make_fn!(need_default);
+  |          ^^^^^^^^^^^^
diff --git a/proc-macro-error/test-crate/tests/ui/multi-error.rs b/proc-macro-error/test-crate/tests/ui/multi-error.rs
new file mode 100644
index 0000000..07fbb03
--- /dev/null
+++ b/proc-macro-error/test-crate/tests/ui/multi-error.rs
@@ -0,0 +1,6 @@
+extern crate test_crate;
+use test_crate::make_fn;
+
+make_fn!(multi1, multi2, _, multi3);
+
+fn main() {}
diff --git a/proc-macro-error/test-crate/tests/ui/multi-error.stderr b/proc-macro-error/test-crate/tests/ui/multi-error.stderr
new file mode 100644
index 0000000..25174d5
--- /dev/null
+++ b/proc-macro-error/test-crate/tests/ui/multi-error.stderr
@@ -0,0 +1,32 @@
+error: multiple error part: multi1
+
+  = note: help message test
+  = help: Option help test
+  = note: I see what you did here...
+
+ --> $DIR/multi-error.rs:4:10
+  |
+4 | make_fn!(multi1, multi2, _, multi3);
+  |          ^^^^^^
+
+error: multiple error part: multi2
+
+  = note: help message test
+  = help: Option help test
+  = note: I see what you did here...
+
+ --> $DIR/multi-error.rs:4:18
+  |
+4 | make_fn!(multi1, multi2, _, multi3);
+  |                  ^^^^^^
+
+error: multiple error part: multi3
+
+  = note: help message test
+  = help: Option help test
+  = note: I see what you did here...
+
+ --> $DIR/multi-error.rs:4:29
+  |
+4 | make_fn!(multi1, multi2, _, multi3);
+  |                             ^^^^^^
diff --git a/proc-macro-error/test-crate/tests/ui/not_proc_macro.rs b/proc-macro-error/test-crate/tests/ui/not_proc_macro.rs
new file mode 100644
index 0000000..e241c5c
--- /dev/null
+++ b/proc-macro-error/test-crate/tests/ui/not_proc_macro.rs
@@ -0,0 +1,4 @@
+use proc_macro_error::proc_macro_error;
+
+#[proc_macro_error]
+fn main() {}
diff --git a/proc-macro-error/test-crate/tests/ui/not_proc_macro.stderr b/proc-macro-error/test-crate/tests/ui/not_proc_macro.stderr
new file mode 100644
index 0000000..52d6a09
--- /dev/null
+++ b/proc-macro-error/test-crate/tests/ui/not_proc_macro.stderr
@@ -0,0 +1,8 @@
+error: #[proc_macro_error] attribute can be used only with a proc-macro
+
+  hint: if you are really sure that #[proc_macro_error] should be applied to this exact function use #[proc_macro_error(allow_not_macro)]
+
+ --> $DIR/not_proc_macro.rs:3:1
+  |
+3 | #[proc_macro_error]
+  | ^^^^^^^^^^^^^^^^^^^
diff --git a/proc-macro-error/test-crate/tests/ui/option_expect.rs b/proc-macro-error/test-crate/tests/ui/option_expect.rs
new file mode 100644
index 0000000..20288ca
--- /dev/null
+++ b/proc-macro-error/test-crate/tests/ui/option_expect.rs
@@ -0,0 +1,6 @@
+extern crate test_crate;
+use test_crate::make_fn;
+
+make_fn!(option_expect);
+
+fn main() {}
diff --git a/proc-macro-error/test-crate/tests/ui/option_expect.stderr b/proc-macro-error/test-crate/tests/ui/option_expect.stderr
new file mode 100644
index 0000000..dd9ecd8
--- /dev/null
+++ b/proc-macro-error/test-crate/tests/ui/option_expect.stderr
@@ -0,0 +1,5 @@
+error: Option::expect_or_abort() test
+ --> $DIR/option_expect.rs:4:1
+  |
+4 | make_fn!(option_expect);
+  | ^^^^^^^^^^^^^^^^^^^^^^^^ in this macro invocation
diff --git a/proc-macro-error/test-crate/tests/ui/result_expect.rs b/proc-macro-error/test-crate/tests/ui/result_expect.rs
new file mode 100644
index 0000000..a42740b
--- /dev/null
+++ b/proc-macro-error/test-crate/tests/ui/result_expect.rs
@@ -0,0 +1,6 @@
+extern crate test_crate;
+use test_crate::make_fn;
+
+make_fn!(result_expect);
+
+fn main() {}
diff --git a/proc-macro-error/test-crate/tests/ui/result_expect.stderr b/proc-macro-error/test-crate/tests/ui/result_expect.stderr
new file mode 100644
index 0000000..c2dd81c
--- /dev/null
+++ b/proc-macro-error/test-crate/tests/ui/result_expect.stderr
@@ -0,0 +1,5 @@
+error: Result::expect_or_abort() test: error
+ --> $DIR/result_expect.rs:4:10
+  |
+4 | make_fn!(result_expect);
+  |          ^^^^^^^^^^^^^
diff --git a/proc-macro-error/test-crate/tests/ui/result_unwrap.rs b/proc-macro-error/test-crate/tests/ui/result_unwrap.rs
new file mode 100644
index 0000000..9b7fb1c
--- /dev/null
+++ b/proc-macro-error/test-crate/tests/ui/result_unwrap.rs
@@ -0,0 +1,6 @@
+extern crate test_crate;
+use test_crate::make_fn;
+
+make_fn!(result_unwrap);
+
+fn main() {}
diff --git a/proc-macro-error/test-crate/tests/ui/result_unwrap.stderr b/proc-macro-error/test-crate/tests/ui/result_unwrap.stderr
new file mode 100644
index 0000000..2e614bd
--- /dev/null
+++ b/proc-macro-error/test-crate/tests/ui/result_unwrap.stderr
@@ -0,0 +1,5 @@
+error: Result::unwrap_or_abort() test
+ --> $DIR/result_unwrap.rs:4:10
+  |
+4 | make_fn!(result_unwrap);
+  |          ^^^^^^^^^^^^^
diff --git a/proc-macro-error/test-crate/tests/ui/unknown_setting.rs b/proc-macro-error/test-crate/tests/ui/unknown_setting.rs
new file mode 100644
index 0000000..d8e58ea
--- /dev/null
+++ b/proc-macro-error/test-crate/tests/ui/unknown_setting.rs
@@ -0,0 +1,4 @@
+use proc_macro_error::proc_macro_error;
+
+#[proc_macro_error(allow_not_macro, assert_unwind_safe, trololo)]
+fn main() {}
diff --git a/proc-macro-error/test-crate/tests/ui/unknown_setting.stderr b/proc-macro-error/test-crate/tests/ui/unknown_setting.stderr
new file mode 100644
index 0000000..a55de0b
--- /dev/null
+++ b/proc-macro-error/test-crate/tests/ui/unknown_setting.stderr
@@ -0,0 +1,5 @@
+error: unknown setting `trololo`, expected one of `assert_unwind_safe`, `allow_not_macro`, `proc_macro_hack`
+ --> $DIR/unknown_setting.rs:3:57
+  |
+3 | #[proc_macro_error(allow_not_macro, assert_unwind_safe, trololo)]
+  |                                                         ^^^^^^^
diff --git a/proc-macro-error/test-crate/tests/ui/unrelated_panic.rs b/proc-macro-error/test-crate/tests/ui/unrelated_panic.rs
new file mode 100644
index 0000000..4863e5b
--- /dev/null
+++ b/proc-macro-error/test-crate/tests/ui/unrelated_panic.rs
@@ -0,0 +1,6 @@
+extern crate test_crate;
+use test_crate::make_fn;
+
+make_fn!();
+
+fn main() {}
diff --git a/proc-macro-error/test-crate/tests/ui/unrelated_panic.stderr b/proc-macro-error/test-crate/tests/ui/unrelated_panic.stderr
new file mode 100644
index 0000000..b852cfd
--- /dev/null
+++ b/proc-macro-error/test-crate/tests/ui/unrelated_panic.stderr
@@ -0,0 +1,7 @@
+error: proc macro panicked
+ --> $DIR/unrelated_panic.rs:4:1
+  |
+4 | make_fn!();
+  | ^^^^^^^^^^^
+  |
+  = help: message: unrelated panic test
author	Robin Krahl <robin.krahl@ireas.org>	2020-01-07 11:18:04 +0000
committer	Daniel Mueller <deso@posteo.net>	2020-01-08 09:20:25 -0800
commit	5e20a29b4fdc8a2d442d1093681b396dcb4b816b (patch)
tree	55ab083fa8999d2ccbb5e921c1ffe52560dca152 /proc-macro-error
parent	203e691f46d591a2cc8acdfd850fa9f5b0fb8a98 (diff)
download	nitrocli-5e20a29b4fdc8a2d442d1093681b396dcb4b816b.tar.gz nitrocli-5e20a29b4fdc8a2d442d1093681b396dcb4b816b.tar.bz2